1//===-- Utility class to test frexp[f|l] ------------------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "src/__support/FPUtil/BasicOperations.h"
10#include "test/UnitTest/FEnvSafeTest.h"
11#include "test/UnitTest/FPMatcher.h"
12#include "test/UnitTest/Test.h"
13#include "utils/MPFRWrapper/MPFRUtils.h"
14
15#include "hdr/math_macros.h"
16
17namespace mpfr = LIBC_NAMESPACE::testing::mpfr;
18
19template <typename T>
20class FrexpTest : public LIBC_NAMESPACE::testing::FEnvSafeTest {
21
22 DECLARE_SPECIAL_CONSTANTS(T)
23
24 static constexpr StorageType HIDDEN_BIT =
25 StorageType(1) << LIBC_NAMESPACE::fputil::FPBits<T>::FRACTION_LEN;
26
27public:
28 typedef T (*FrexpFunc)(T, int *);
29
30 void testSpecialNumbers(FrexpFunc func) {
31 int exponent;
32 ASSERT_FP_EQ(aNaN, func(aNaN, &exponent));
33 ASSERT_FP_EQ(inf, func(inf, &exponent));
34 ASSERT_FP_EQ(neg_inf, func(neg_inf, &exponent));
35
36 ASSERT_FP_EQ(0.0, func(0.0, &exponent));
37 ASSERT_EQ(exponent, 0);
38
39 ASSERT_FP_EQ(-0.0, func(-0.0, &exponent));
40 ASSERT_EQ(exponent, 0);
41 }
42
43 void testPowersOfTwo(FrexpFunc func) {
44 int exponent;
45
46 EXPECT_FP_EQ(T(0.5), func(T(1.0), &exponent));
47 EXPECT_EQ(exponent, 1);
48 EXPECT_FP_EQ(T(-0.5), func(T(-1.0), &exponent));
49 EXPECT_EQ(exponent, 1);
50
51 EXPECT_FP_EQ(T(0.5), func(T(2.0), &exponent));
52 EXPECT_EQ(exponent, 2);
53 EXPECT_FP_EQ(T(-0.5), func(T(-2.0), &exponent));
54 EXPECT_EQ(exponent, 2);
55
56 EXPECT_FP_EQ(T(0.5), func(T(4.0), &exponent));
57 EXPECT_EQ(exponent, 3);
58 EXPECT_FP_EQ(T(-0.5), func(T(-4.0), &exponent));
59 EXPECT_EQ(exponent, 3);
60
61 EXPECT_FP_EQ(T(0.5), func(T(8.0), &exponent));
62 EXPECT_EQ(exponent, 4);
63 EXPECT_FP_EQ(T(-0.5), func(T(-8.0), &exponent));
64 EXPECT_EQ(exponent, 4);
65
66 EXPECT_FP_EQ(T(0.5), func(T(16.0), &exponent));
67 EXPECT_EQ(exponent, 5);
68 EXPECT_FP_EQ(T(-0.5), func(T(-16.0), &exponent));
69 EXPECT_EQ(exponent, 5);
70
71 EXPECT_FP_EQ(T(0.5), func(T(32.0), &exponent));
72 EXPECT_EQ(exponent, 6);
73 EXPECT_FP_EQ(T(-0.5), func(T(-32.0), &exponent));
74 EXPECT_EQ(exponent, 6);
75 }
76
77 void testSomeIntegers(FrexpFunc func) {
78 int exponent;
79
80 EXPECT_FP_EQ(T(0.75), func(T(24.0), &exponent));
81 EXPECT_EQ(exponent, 5);
82 EXPECT_FP_EQ(T(-0.75), func(T(-24.0), &exponent));
83 EXPECT_EQ(exponent, 5);
84
85 EXPECT_FP_EQ(T(0.625), func(T(40.0), &exponent));
86 EXPECT_EQ(exponent, 6);
87 EXPECT_FP_EQ(T(-0.625), func(T(-40.0), &exponent));
88 EXPECT_EQ(exponent, 6);
89
90 EXPECT_FP_EQ(T(0.78125), func(T(800.0), &exponent));
91 EXPECT_EQ(exponent, 10);
92 EXPECT_FP_EQ(T(-0.78125), func(T(-800.0), &exponent));
93 EXPECT_EQ(exponent, 10);
94 }
95
96 void testRange(FrexpFunc func) {
97 using StorageType = typename FPBits::StorageType;
98 constexpr StorageType COUNT = 100'000;
99 constexpr StorageType STEP = STORAGE_MAX / COUNT;
100 for (StorageType i = 0, v = 0; i <= COUNT; ++i, v += STEP) {
101 T x = FPBits(v).get_val();
102 if (isnan(x) || isinf(x) || x == 0.0l)
103 continue;
104
105 mpfr::BinaryOutput<T> result;
106 result.f = func(x, &result.i);
107
108 ASSERT_TRUE(LIBC_NAMESPACE::fputil::abs(result.f) < 1.0);
109 ASSERT_TRUE(LIBC_NAMESPACE::fputil::abs(result.f) >= 0.5);
110 ASSERT_MPFR_MATCH(mpfr::Operation::Frexp, x, result, 0.0);
111 }
112 }
113};
114
115#define LIST_FREXP_TESTS(T, func) \
116 using LlvmLibcFrexpTest = FrexpTest<T>; \
117 TEST_F(LlvmLibcFrexpTest, SpecialNumbers) { testSpecialNumbers(&func); } \
118 TEST_F(LlvmLibcFrexpTest, PowersOfTwo) { testPowersOfTwo(&func); } \
119 TEST_F(LlvmLibcFrexpTest, SomeIntegers) { testSomeIntegers(&func); } \
120 TEST_F(LlvmLibcFrexpTest, InRange) { testRange(&func); }
121

source code of libc/test/src/math/FrexpTest.h